Répondre :
bonjour
a. jour 1 = 80 x 2/5 = 32 km
b . jour 1 il reste 3 /5
c . jour 2 = 3/5 x 1/2 = 3 /10
d. jour 3 = 1 - ( 2/5 + 3/10 ) = 10/10 - ( 4/10 + 3 /10 ) = 10/10 - 7/10 = 3/10
bonjour
a. jour 1 = 80 x 2/5 = 32 km
b . jour 1 il reste 3 /5
c . jour 2 = 3/5 x 1/2 = 3 /10
d. jour 3 = 1 - ( 2/5 + 3/10 ) = 10/10 - ( 4/10 + 3 /10 ) = 10/10 - 7/10 = 3/10